ISSN:0364-9024    

DOI:10.1002/jgt.3190070302

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1983

数据来源: WILEY

摘要:

AbstractA complete equipartite graph is a complete multipartite graph such that the color classes are equinumerous. An isomorphic factorization of a graph is a partition of the line set into disjoint isomorphic parts. It is shown that an isomorphic factorization of the complete equipartite graph intotisomorphic subgraphs exists whenever the total number of lines is divisible byt.

ISSN:0364-9024    

DOI:10.1002/jgt.3190070303

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1983

数据来源: WILEY

摘要:

AbstractThis paper deals with the limiting distribution of the level number of the jth leaf of a planted plane tree (where leaves are enumerated from left to right) for the so‐called “simply generated families” introduced by Meir and Moon. The mathematical apparatus is determined by the idea of an asymptotic analysis of a given sequence of numbers by studying the location and nature of the singularities of appropriate generating func

ISSN:0364-9024    

DOI:10.1002/jgt.3190070304

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1983

数据来源: WILEY

摘要:

AbstractIfGis a bipartite graph with bipartitionA, Bthen letGm,n(A, B)be obtained fromGby replacing each vertexaofAby an independent seta1, …,am, each vertexbofBby an independent setb1,…,bn, and each edgeabofGby the complete bipartite graph with edgesaibj(1 ≤i ≤ mand 1 ≤j ≤ n). WheneverGhas certain types of spanning forests, then cellular embeddings ofGin surfacesSmay be lifted to embeddings ofGm,n(A, B)having faces of the same sizes as those ofGinS. These results are proved by the technique of “excess‐current graphs.” They include new genus embeddings for a large class of

ISSN:0364-9024    

DOI:10.1002/jgt.3190070305

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1983

数据来源: WILEY

摘要:

AbstractProblems involving the dismantling of a digraph (graph) by removal of arcs (edges) are investigated. Some of these problems have good characterizations related to the familiar results about Euler trails, others are NP‐complet

ISSN:0364-9024    

DOI:10.1002/jgt.3190070306

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1983

数据来源: WILEY

摘要:

AbstractAk‐flow is an assignment of edge directions and integer weights in the range 1, ….,k– 1 to the edges of an undirected graph so that ateach vertex the flow in is equal to the flow out. This paper gives a polynomial algorithm for finding a 6‐flow that applies uniformly to each graph. The algorithm specializes to give a 5‐flow for plan

ISSN:0364-9024    

DOI:10.1002/jgt.3190070307

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1983

数据来源: WILEY

摘要:

AbstractThere are three types of oriented 2‐paths. Necessary and sufficient conditions are given under which all oriented 2‐paths of the same type and with vertices labeled 1, 2,….,ncan be partitioned into copies of the complete symmetric directed graph withnver

ISSN:0364-9024    

DOI:10.1002/jgt.3190070308

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1983

数据来源: WILEY

摘要:

AbstractThe Gyárfás‐Lehel tree‐packing conjecture asserts that any sequenceT1,T2, …,Tn−1of trees with 1, 2, …,n‐ 1 edges packs into the complete graphKnonnvertices. The present paper examines two conjectures that jointly imply the Gyárfás‐Lehel conjecture: 1. Forneven, anyT1,T3, …,Tn−1pack into the half‐complete graph Hn onnvertices.2. Fornodd, any T2, T4, …,Tn−1pack into the half‐complete graph Hn onnvertices.TheHnare uniquely defined by their degree sequences:HnandHn+1are complements inKn+1. It is shown thatHnandTn+1pack intoHn+2ifTn+1is a double star, unimodal triple star, interior‐3 caterpillar, or scorpion. Hence Conjectures 1 and 2 are true for these specialized types of trees. The conjectures are also valid for all trees whenn≤ 9, so that the Gyár

ISSN:0364-9024    

DOI:10.1002/jgt.3190070309

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1983

数据来源: WILEY

ISSN:0364-9024    

DOI:10.1002/jgt.3190070301

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1983

数据来源: WILEY